With the continuous development of integrated circuit (IC) technologies, the development trend for electronic products is moving towards more miniaturized and intelligent structures with high performance and high reliability. IC packaging not only has a direct impact on the performance of the integrated circuits, electronic modules, and even the systems, but also restricts the miniaturization, low-cost, and reliability of electronic systems. As the IC chip size keeps decreasing and the integration degree keeps increasing, higher and higher requirements for IC packaging technology are raised by the electronics industry.
Chinese patent publication number CN1747156C discloses a packaging substrate. The disclosed packaging substrate includes: a substrate having a surface; a ball pad located on the substrate surface; a solder mask layer formed on the surface of the substrate, with at least one opening to expose the ball pad; and a patterned metal reinforcing layer formed on the ball pad along the sidewall of the solder mask layer opening. However, when such packaging substrate is used, the system-level packaging integration degree may be still undesired.
Fan-out wafer level packaging is one type of wafer-level packaging technologies. For example, Chinese patent application 200910031885.0 disclosed one wafer-level fan-out chip packaging method, the process steps including: covering the circular carrier substrate surface with a stripping film and a thin film dielectric layer I sequentially, and forming photolithography pattern openings I on the thin film dielectric layer I; forming metal electrodes connecting the substrate and re-wiring metal wires on the photolithography pattern openings I and its surface; covering the surfaces of metal electrodes connecting the substrate, re-wiring metal wires, and thin film dielectric layer I with thin-film dielectric layer II, and forming photolithography pattern openings II on the thin film dielectric layer II; constructing metal electrodes connecting chips on the photolithography pattern openings II; flipping the chips onto the metal electrodes and performing plastic encapsulation and curing to form a packaging structure with a plastic sealant layer; separating the circular carrier substrate and the striping film from the packaging structure with the plastic sealant layer to form a plastic-encapsulated wafer; planting and reflowing balls to form solder balls or bumps; cutting the plastic-encapsulated wafer into individual finished fan-out chip structures.
However, the final products made by the above packaging method may only support a single chip function. To achieve complete system functions, peripheral circuits including capacitors, inductors or resistors may need to be added at the outside of the final products. Further, the above method may be unable to be applied to manufacturing of multi-layer packaging structures with complex connections. Further, when such packaging method is used, the system-level packaging integration degree may be still undesired.
On the other hand, with the trend for light, thin, short, and small products as well as increasingly high demand for system-level functionalities, the integration degree of system-level packaging needs to be further improved. The disclosed methods and systems are directed to solve one or more problems set forth above and other problems.